Correct Answer: Option 2 – Earth rotates on its axis

Each day the Earth will have moved one 365th of its orbit around the Sun. The result is that we see some different stars coming into view as the Earth spins from night to night and other stars move out of view. On a spinning Earth, observers looking further away from the center of the spin axis see the wallpaper of the sky rush around them in a day, while observers looking up near the spin axes (the poles) see the wallpaper move less and even see that stationary point which is like the cloud from the merry-go-round example. Only over the North Pole is there a star roughly at that stationary point. It is called Polaris, the Pole star.

Important points to stress include:

• It is the rotation of the Earth which makes the stars appear to move through the sky
• Polaris, The North Star, is nearly directly above the North Pole and the Earth's axis of rotation, so all the stars seem to move around it
• The motion of the stars is just as predictable as that of the Sun, so they too can be used to measure time

Based on these arguments, the rest of the  options are incorrect

Correct Answer: Option 1 – Main sequence star

Main sequence stars are characterized by the source of their energy. They are all undergoing fusion of hydrogen into helium within their cores. The rate at which they do this and the amount of fuel available depends upon the mass of the star. Mass is the key factor in determining the lifespan of a main sequence star, its size and its luminosity. Stars on the main sequence also appear to be unchanging for long periods of time. Any model of such stars must be able to account for their stability.

Algol is a main sequence dwarf star fusing hydrogen in its core, though it is 3.5 times more massive, when compared to sun. Algol (Beta Persei) is the name of a star in the constellation Perseus. Algol is a trinary star system, containing 3 stars, Algol A, a star of spectral type B (blue in color), Algol B is K-type (orange), and Algol C is A-type (blue-white). Algol is a variable star, meaning it undergoes wide variations in its brightness over time. It is one of the few variable stars that does not have its variability linked with novae. Its changes in brightness follow a fixed rhythm which repeats every 68 hours, 49 minutes. It was also the first eclipsing binary to be discovered (a binary star system where each star can eclipse the other). Algol is located 93 light years from Earth. The star's name is derived from the Arabic al-ghul, which means "The Ghoul". Due to its changes in brightness and its name meaning, it was called "The Demon Star". Algol in the constellation Perseus is said to represent the eye of the Gorgon Medusa (her glance had the power to turn any living creature to stone).

Rest options are incorrect based on the above information

Correct Answer: Option 4 – over 10

About 15 billion years ago a tremendous explosion started the expansion of the universe. This explosion is known as the Big Bang. At the point of this event all of the matter and energy of space was contained at one point. What existed prior to this event is completely unknown and is a matter of pure speculation. This occurrence was not a conventional explosion but rather an event filling all of space with all of the particles of the embryonic universe rushing away from each other. The Big Bang actually consisted of an explosion of space within itself unlike an explosion of a bomb were fragments are thrown outward. The galaxies were not all clumped together, but rather the Big Bang lay the foundations for the universe.

The origin of the Big Bang theory can be credited to Edwin Hubble. Hubble made the observation that the universe is continuously expanding. He discovered that a galaxy's velocity is proportional to its distance. Galaxies that are twice as far from us move twice as fast. Another consequence is that the universe is expanding in every direction. This observation means that it has taken every galaxy the same amount of time to move from a common starting position to its current position. Just as the Big Bang provided a foundation of the universe, Hubble's observations provided for the foundation of the Big Bang theory.

Correct Answer: Option 2 – Earth orbits the sun

Constellations are recognizable patterns formed in the sky by stars. Generally, the stars in a given constellation are not related to one another except for lying in the same direction from our point of view on planet Earth - if we could get a "top view" of them, some would be relatively close to us and some very far away, despite falling in the same constellation. Lyra is a small constellation, but its principal star, Vega, is one of the brightest in the sky.

The skies are divided into 4 sections - circumpolar, north of the ecliptic, along the ecliptic, and south of the ecliptic - and give their visibility by month. This is largely controlled by the fact that earth orbits the sun.

Correct Answer: Option 1 – rotates on its axis

The Coriolis effect is an apparent deflection of moving objects when they are viewed from a rotating reference frame. Movements of air in the atmosphere and water in the ocean are notable examples of this behavior: rather than flowing directly from areas of high pressure to low pressure, as they would on a non-rotating planet, winds and currents tend to flow to the right of this direction north of the equator, and to the left of this direction south of the equator. This effect is responsible for the rotation of large cyclones. Once air has been set in motion by the pressure gradient force, it undergoes an apparent deflection from its path, as seen by an observer on the earth. This apparent deflection is called the "Coriolis force" and is a result of the earth's rotation.

Correct Answer: Option 2

The star is moving away appears to be red in color because of Doppler Effect. The Doppler Effect is waves (in this case light) will be compressed in front of a moving object and stretched behind the object. This stretching creates a long wavelength. Red light has a long wavelength (the longest of visible light), so we call this stretching red shift

Correct Answer: Option 2 - B

According to the diagram, New York State is exposed to night (i.e. on the side of the earth not exposed to sunlight), hence, the moon is seen as in diagram 2 when it is at position B.

Correct Answer: Option 1 – 20⁰ N

Polaris, the North Star, is located directly above the North Pole. As a result, the altitude of Polaris at any location in the northern hemisphere is equal to the latitude of the observer. In the diagram, the altitude of Polaris to the observer is 20°. The position of the observer is therefore 20° North

Correct Answer: Option 3 – 12 noon

According to the diagram, the surface of the earth from where Hermes is visible, is experiencing darkness or near darkness such as sunrise, sunset or 12 midnight; leaving the part of the earth having day light not having the view of Hermes. Hence, option 3 is the correct answer.

Correct Answer: Option 3 – Hermes has a longer period of revolution than all of the planets shown

The study by astronomers has revealed the above fact about Hermes.